It is generally old, as shown in U.S. Pat. Nos. 3,420,308 and 3,893,717, to support an inner casing in a well from an outer casing by means of a resiliently self-expandable and contractible C-shaped spring support ring. However, the body of the casing hanger is generally provided with a plurality of fluid flow slots which must be sufficiently large to provide the desired fluid return area. The use of large number and area of fluid flow slots reduces the bearing area between the support spring and the hanger body which results in a lower load capacity for the hanger. In addition, the ring blocks at least some of the flow slots and reduces the fluid return area.
The present invention is directed to an improved casing hanger assembly which has a sufficient fluid flow slot area to accommodate the necessary fluid return, but yet provide a larger bearing area between the support spring and the hanger body which will provide a higher load capacity for the casing hanger.